Can’t Stop Eating Junk Food? Here’s Why

Written by Tamara Willner
Medically reviewed by 

8 min read
Last updated November 2019

Cravings for junk food are a common reason that people ‘fall off the wagon’ with their healthy eating plans. They can lead to unhealthy eating habits and be the biggest obstacle to weight loss.

Have you ever found yourself craving a second helping of dessert after a filling dinner, or finishing a sharing-size bag of crisps or chocolate? You are not alone! It can be incredibly hard with some foods to know when to say stop.

What is it that makes certain foods seemingly irresistible? What keeps us coming back for more, even when we know we’re full? What makes us binge on foods we know are bad for us?

Isn’t it down to willpower?

We often beat ourselves up for giving in to our junk food cravings, but it’s no accident that these foods are so hard to resist. The food industry engineer foods to taste the best they possibly can with the goal of overriding our internal ‘stop’ signals and encouraging us to buy more.

So what’s the winning formula? If there’s one man to thank (or curse) for figuring out what makes us reach for another slice, it’s Howard Moskowitz, an American market researcher known for creating addictive flavour combinations that fly off the shelves.

The story of how food giants refuse to listen to concerns about obesity, and how junk food is engineered by individuals like Moskowitz to evoke maximum pleasure, is set out in this New York Times article.

Key points:

  • Resisting junk food cravings is not a case of willpower.
  • Junk foods are specially engineered to target our pleasure receptors in the brain.

How junk food is engineered to be ‘just right’

Ever noticed that no matter how full you feel after a meal, you can always make room for dessert? This is most likely down to a psychological phenomenon called ‘sensory-specific satiety’.

As we consume more of a particular flavour, our taste buds slowly get more and more tired of it, and we stop eating that food. When presented with a new flavour, we get more reward from it, and so we continue eating. We can see this concept in action at an all-you-eat buffet; we’re likely to eat more because there is a variety of flavours to keep our taste buds interested!

However, our taste system can be tricked when salt, fat, and sugar are carefully combined in expertly measured amounts to be ‘just right’. At this point, we keep coming back for more, even when our bodies are trying to tell us to stop because we keep experiencing pleasure.

Moskowitz coined this as the ‘bliss point’ – the exact measures of fat, sugar, and salt that make our taste buds tingle and override the brain’s natural ‘stop’ signals. This bliss point plays a significant role in why we crave certain addictive foods, such as ice cream and crisps. Even in the most strong-willed individuals, these cravings can seem impossible to resist.

Graph illustrating that pleasure diminishes faster for normal food compared with bliss-point foods.

Key points:

  • The more we eat one type of food the less rewarding we find the taste.
  • Foods that hit the bliss point override the brain’s natural ‘stop’ signal and keep providing us with pleasure.
  • This leads to us wanting more and more of that enticing food.

The science behind the bliss point

So what’s going on when we consume foods engineered like this? Why can’t we get enough?

Our bodies respond to foods that hit the bliss point by triggering reward pathways in our brain and encouraging dopamine signalling. Dopamine is a neurotransmitter (chemical messenger) in the brain that is involved with feelings of euphoria, bliss, motivation, and pleasure.

The result of this is a feeling of pleasure, that acts like a high, and we keep on coming back for more. This leads to a perpetual cycle of cravings, eating more junk, weight gain, and more cravings!

In a TED talk on the topic, psychiatrist Judson Brewer points out that this cycle is built upon context-dependent memory. Our brain remembers what actions make us feel good, such as eating chocolate. Then when we feel bad for whatever reason, our brain says ‘eating chocolate might help’, and we are driven to eat chocolate. After we repeat this process enough, it becomes an automatic habit.

Of course, food brings pleasure in many other ways; for example, by producing feelings of nostalgia or enjoying food socially with family and friends. There is absolutely nothing wrong with this, but there is a difference between enjoying food and building unhealthy habits by overeating foods that hit our bliss point.

A study demonstrated that when rats eat sugars and fats separately, their brains send them messages to stop when they’re full. However, when they’re combined in a deliciously decadent duo, their pleasure receptors went into overdrive, overpowering that internal stop switch. On top of this, the more bliss-point foods the rats consumed, the more they had to eat to get that same pleasure hit next time.

Diagram illustrating the effects of eating sugar and fat alone vs. sugar and fat combined.

Research has shown that sugar encourages the same addictive behaviour as some drugs, overriding our ability to realise when we’re full. So it’s no wonder that only eating one biscuit is challenging when sugar is combined with salt and fat to reach the bliss point.

Key points:

  • Our bodies respond to foods that hit the bliss point by triggering reward pathways in our brain and encouraging dopamine signalling.
  • Our brain remembers what foods make us feel good and triggers a craving for these foods when we feel bad.
  • There is nothing wrong with enjoying food, but binging as a result of craving, for any reason, is usually down to the bliss point.

What foods are the main culprits?

You might be surprised about which foods are the culprits. Some obvious bliss-point items include:

  • Cakes
  • Biscuits
  • Doughnuts
  • Ice cream
  • Crisps
  • Muffins
  • Chocolate
  • Sweets

However, it’s more than just the obvious foods. Next time you pick up a jar of tomato sauce at the supermarket, stop to take a look at the ingredients and see just how much sugar and salt are hidden inside. Less obvious bliss-point foods include:

  • Sauces
  • Dressings
  • Dips
  • Soups
  • Bread
  • Cereal bars

Surprisingly, all these products can contain that longed-for trio of salt, sugar, and fat that keeps us coming back for more.

Key points:

  • Avoiding the obvious foods, like cakes and biscuits, can help to reduce your future cravings for these foods.
  • Surprisingly, many unexpected foods have also been engineered to leave you wanting more.

Top tips to reduce junk food cravings

1) Break the habit

In the TED talk mentioned above, Judson Brewer explains that the best way to break a habit, like junk food eating, is to become aware of what is happening in your mind and body when we crave.

Rather than trying to ignore your cravings, try getting curious and recognising how you feel when you crave or eat a particular food. Understanding what happens when we eat junk food helps us to step back and become less interested in this habit.

Next time you have a craving for some junk food, getting curious about what’s happening (‘am I feeling sad, stressed, or hungry?’) will help you let the craving go. Then, repeating this process enough will help you break the habit of feeling compelled to eat from cravings. Consider finding other avenues for emotional release if you notice that you crave junk food when you are stressed or sad. Walking, music, or writing in a journal can all be great stress busters.

2) Eat junk food mindfully

Mindful eating can help us break habits while still enjoying junk food occasionally. This involves focusing solely on the taste and texture of the food you are eating and any sensations you feel in that present moment.

Occasionally consuming junk food is part of life. The key is to eat it free from distractions (e.g. not in front of the tv or at your desk at work) and enjoy it so that you feel satisfied without overeating it. Eating mindfully can help us tune into our internal hunger signals and prevent them from being overridden.

3) Build balanced meals

Building balanced meals can help us feel satisfied and reduce the risk of junk food cravings in between meals. Opt for:

  • Fresh vegetables, (e.g. spinach and peppers).
  • Unprocessed meat and fish (e.g. chicken or salmon).
  • Wholegrain carb options (e.g. brown rice or rye bread).

Here is an example 7-day diet plan that is satisfying and focuses on balanced, healthy meals.

4) Be aware of bliss-point foods

Try to be aware of unexpected foods that we use every day (e.g. tomato sauce) which has also been engineered to have a bliss-point. Real food doesn’t need fussy engineering and fancy packaging to taste great. Try experimenting with making your food to replace shop bought ones with added sugars and salts.

For instance, you can easily make your tomato sauce using chopped tinned tomatoes, herbs, and garlic. Eating real food will not override hunger signals, nor overstimulate brain-reward systems, and still tastes delicious.

5) Sleep

Sleep is often overlooked when we discuss junk food cravings. However, research has demonstrated that the more sleep deprived we are, the more hungry we feel. On top of this, when we are tired we are much more likely to crave and eat energy dense, sugar, and fat filled junk foods as opposed to healthy snacks. Getting 8-9 hours of sleep, compared to 6-7 hours, can massively reduce the risk of junk food cravings.

Key points:

  • Being curious and mindful of what happens when we crave junk food, and how we feel when we eat it, can help us break the habit of craving.
  • Recognising bliss-point foods and building balanced meals can reduce the number of cravings we have for junk foods.
  • A lack of sleep increases our hunger levels and influences our food choices.

Take home message

  • Binging as a result of junk food cravings is not down to willpower.
  • The food industry has invested a lot of money to find the perfect combination of salt, fat, and sugar that maximises pleasure.
  • This bliss point works by triggering reward pathways in our brain and encouraging dopamine (pleasure hormone) signalling.
  • Our brain then learns that these foods make us feel good, and we then crave them when we feel bad.
  • Obvious foods, such as chocolate and cakes, have been engineered to reach the bliss-point when we eat them.
  • Less obvious foods, such as tomato sauces and bread, have also undergone similar processing sometimes!
  • Being curious and mindful of how you feel when you eat junk foods can help to break the habit.
  • Eating balanced meals and sleeping well can massively reduce cravings for junk food.
Write a response
Sarah Steines
4 October, 2019

Fascinating, and well written. Thankyou.


Joanna Wilderspin
11 October, 2019

Thank you – very interesting Reading. I was just feeling like a mid afternoon biscuit, but Instead, I read your article first, had a drink of water and an apple. No biscuit eaten. Feel very happy now as I have been distracted from that ‘snacking’ feeling.


Shirley Endall
11 October, 2019

I found this article very interesting and I can recognise some parts of my sweet cravings written in your article. I do however need to go back and read it again as there is too much info for my brain in one reading🤗


Phyllis Gallagher
14 November, 2019

Sadly, stress can make one turn to sugar ie chocolate and crisps for comfort. However, like your article suggests, we should train our brain to think more about what we are consuming into our bodies. A very good article. Thank you.